Struct ZeroTriePerfectHash

#[repr(transparent)]
pub struct ZeroTriePerfectHash<Store: ?Sized> { /* private fields */ }

A data structure that compactly maps from byte strings to integers.

For more information, see ZeroTrie.

Examples

use litemap::LiteMap;
use zerotrie::ZeroTriePerfectHash;

let mut map = LiteMap::<&[u8], usize>::new_vec();
map.insert("foo".as_bytes(), 1);
map.insert("bår".as_bytes(), 2);
map.insert("båzzøø".as_bytes(), 3);

let trie = ZeroTriePerfectHash::try_from(&map)?;

assert_eq!(trie.get("foo".as_bytes()), Some(1));
assert_eq!(trie.get("bår".as_bytes()), Some(2));
assert_eq!(trie.get("båzzøø".as_bytes()), Some(3));
assert_eq!(trie.get("bazzoo".as_bytes()), None);

Implementations

impl<Store> ZeroTriePerfectHash<Store>

pub const fn into_zerotrie(self) -> ZeroTrie<Store>

Wrap this specific ZeroTrie variant into a ZeroTrie.

impl<Store> ZeroTriePerfectHash<Store>

pub const fn from_store(store: Store) -> Self

Create a trie directly from a store.

If the store does not contain valid bytes, unexpected behavior may occur.

pub fn take_store(self) -> Store

Takes the byte store from this trie.

pub fn convert_store<X: From<Store>>(self) -> ZeroTriePerfectHash<X>

Converts this trie’s store to a different store implementing the From trait.

For example, use this to change ZeroTriePerfectHash<Vec<u8>> to ZeroTriePerfectHash<Cow<[u8]>>.

Examples

use std::borrow::Cow;
use zerotrie::ZeroTriePerfectHash;

let trie: ZeroTriePerfectHash<Vec<u8>> = ZeroTriePerfectHash::from_bytes(b"abc\x85").to_owned();
let cow: ZeroTriePerfectHash<Cow<[u8]>> = trie.convert_store();

assert_eq!(cow.get(b"abc"), Some(5));

impl<Store> ZeroTriePerfectHash<Store>

where Store: AsRef<[u8]> + ?Sized,

pub fn get<K>(&self, key: K) -> Option<usize>

where K: AsRef<[u8]>,

Queries the trie for a string.

pub fn is_empty(&self) -> bool

Returns true if the trie is empty.

pub fn byte_len(&self) -> usize

Returns the size of the trie in number of bytes.

To get the number of keys in the trie, use .iter().count():

use zerotrie::ZeroTriePerfectHash;

// A trie with two values: "abc" and "abcdef"
let trie: &ZeroTriePerfectHash<[u8]> = ZeroTriePerfectHash::from_bytes(b"abc\x80def\x81");

assert_eq!(8, trie.byte_len());
assert_eq!(2, trie.iter().count());

pub fn as_bytes(&self) -> &[u8]

Returns the bytes contained in the underlying store.

pub fn as_borrowed(&self) -> &ZeroTriePerfectHash<[u8]>

Returns this trie as a reference transparent over a byte slice.

pub fn as_borrowed_slice(&self) -> ZeroTriePerfectHash<&[u8]>

Returns a trie with a store borrowing from this trie.

impl<Store> ZeroTriePerfectHash<Store>

where Store: AsRef<[u8]> + ?Sized,

pub fn to_owned(&self) -> ZeroTriePerfectHash<Vec<u8>>

Converts a possibly-borrowed $name to an owned one.

✨ Enabled with the alloc Cargo feature.

Examples

use zerotrie::ZeroTriePerfectHash;

let trie: &ZeroTriePerfectHash<[u8]> = ZeroTriePerfectHash::from_bytes(b"abc\x85");
let owned: ZeroTriePerfectHash<Vec<u8>> = trie.to_owned();

assert_eq!(trie.get(b"abc"), Some(5));
assert_eq!(owned.get(b"abc"), Some(5));

pub fn iter(&self) -> impl Iterator<Item = (Vec<u8>, usize)> + '_

Returns an iterator over the key/value pairs in this trie.

✨ Enabled with the alloc Cargo feature.

Examples

use zerotrie::ZeroTriePerfectHash;

// A trie with two values: "abc" and "abcdef"
let trie: &ZeroTriePerfectHash<[u8]> = ZeroTriePerfectHash::from_bytes(b"abc\x80def\x81");

let mut it = trie.iter();
assert_eq!(it.next(), Some(("abc".into(), 0)));
assert_eq!(it.next(), Some(("abcdef".into(), 1)));
assert_eq!(it.next(), None);

impl ZeroTriePerfectHash<[u8]>

pub fn from_bytes(trie: &[u8]) -> &Self

Casts from a byte slice to a reference to a trie with the same lifetime.

If the bytes are not a valid trie, unexpected behavior may occur.

impl ZeroTriePerfectHash<Vec<u8>>

pub(crate) fn try_from_tuple_slice( items: &[(&ByteStr, usize)], ) -> Result<Self, Error>

impl<Store> ZeroTriePerfectHash<Store>

where Store: AsRef<[u8]> + ?Sized,

pub fn to_btreemap(&self) -> BTreeMap<Vec<u8>, usize>

Exports the data from this ZeroTrie type into a BTreeMap.

✨ Enabled with the alloc Cargo feature.

Examples

use zerotrie::ZeroTriePerfectHash;
use std::collections::BTreeMap;

let trie = ZeroTriePerfectHash::from_bytes(b"abc\x81def\x82");
let items = trie.to_btreemap();

assert_eq!(items.len(), 2);

let recovered_trie: ZeroTriePerfectHash<Vec<u8>> = items
    .into_iter()
    .collect();
assert_eq!(trie.as_bytes(), recovered_trie.as_bytes());

pub(crate) fn to_btreemap_bytes(&self) -> BTreeMap<Box<[u8]>, usize>

Trait Implementations

impl<Store> AsRef<ZeroTriePerfectHash<[u8]>> for ZeroTriePerfectHash<Store>

where Store: AsRef<[u8]> + ?Sized,

fn as_ref(&self) -> &ZeroTriePerfectHash<[u8]>

Converts this type into a shared reference of the (usually inferred) input type.

impl Borrow<ZeroTriePerfectHash<[u8]>> for ZeroTriePerfectHash<&[u8]>

fn borrow(&self) -> &ZeroTriePerfectHash<[u8]>

Immutably borrows from an owned value.

impl Borrow<ZeroTriePerfectHash<[u8]>> for ZeroTriePerfectHash<Box<[u8]>>

fn borrow(&self) -> &ZeroTriePerfectHash<[u8]>

Immutably borrows from an owned value.

impl Borrow<ZeroTriePerfectHash<[u8]>> for ZeroTriePerfectHash<Vec<u8>>

fn borrow(&self) -> &ZeroTriePerfectHash<[u8]>

Immutably borrows from an owned value.

impl<Store: Clone + ?Sized> Clone for ZeroTriePerfectHash<Store>

fn clone(&self) -> ZeroTriePerfectHash<Store>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<Store: Debug + ?Sized> Debug for ZeroTriePerfectHash<Store>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<Store: Default + ?Sized> Default for ZeroTriePerfectHash<Store>

fn default() -> ZeroTriePerfectHash<Store>

Returns the “default value” for a type.

impl<Store> From<&ZeroTriePerfectHash<Store>> for BTreeMap<Vec<u8>, usize>

where Store: AsRef<[u8]> + ?Sized,

fn from(other: &ZeroTriePerfectHash<Store>) -> Self

Converts to this type from the input type.

impl<'a, K> FromIterator<(K, usize)> for ZeroTriePerfectHash<Vec<u8>>

where K: AsRef<[u8]>,

fn from_iter<T: IntoIterator<Item = (K, usize)>>(iter: T) -> Self

Creates a value from an iterator.

impl<Store: PartialEq + ?Sized> PartialEq for ZeroTriePerfectHash<Store>

fn eq(&self, other: &ZeroTriePerfectHash<Store>) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl ToOwned for ZeroTriePerfectHash<[u8]>

fn to_owned(&self) -> Self::Owned

This impl allows ZeroTriePerfectHash to be used inside of a Cow.

Note that it is also possible to use ZeroTriePerfectHash<ZeroVec<u8>> for a similar result.

✨ Enabled with the alloc Cargo feature.

Examples

use std::borrow::Cow;
use zerotrie::ZeroTriePerfectHash;

let trie: Cow<ZeroTriePerfectHash<[u8]>> = Cow::Borrowed(ZeroTriePerfectHash::from_bytes(b"abc\x85"));
assert_eq!(trie.get(b"abc"), Some(5));

type Owned = ZeroTriePerfectHash<Box<[u8]>>

The resulting type after obtaining ownership.

fn clone_into(&self, target: &mut Self::Owned)

Uses borrowed data to replace owned data, usually by cloning.

impl<'a, K> TryFrom<&'a BTreeMap<K, usize>> for ZeroTriePerfectHash<Vec<u8>>

where K: Borrow<[u8]>,

type Error = Error

The type returned in the event of a conversion error.

fn try_from(map: &'a BTreeMap<K, usize>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'zf, Store1, Store2> ZeroFrom<'zf, ZeroTriePerfectHash<Store1>> for ZeroTriePerfectHash<Store2>

where Store2: ZeroFrom<'zf, Store1>,

fn zero_from(other: &'zf ZeroTriePerfectHash<Store1>) -> Self

Clone the other C into a struct that may retain references into C.

impl<S: ?Sized> ZeroTrieWithOptions for ZeroTriePerfectHash<S>

Branch nodes could be either binary search or PHF.

const OPTIONS: ZeroTrieBuilderOptions

impl<Store: Copy + ?Sized> Copy for ZeroTriePerfectHash<Store>

impl<Store: Eq + ?Sized> Eq for ZeroTriePerfectHash<Store>

impl<Store: ?Sized> StructuralPartialEq for ZeroTriePerfectHash<Store>